title: Role of hyperosmolarity in the pathogenesis and management of dry eye disease: proceedings of the OCEAN group meeting.
abstract: Dry eye disease (DED), a multifactorial disease of the tears and ocular surface, is common and has a significant impact on quality of life. Reduced aqueous tear flow and/or increased evaporation of the aqueous tear phase leads to tear hyperosmolarity, a key step in the vicious circle of DED pathology. Tear hyperosmolarity gives rise to morphological changes such as apoptosis of cells of the conjunctiva and cornea, and triggers inflammatory cascades that contribute to further cell death, including loss of mucin-producing goblet cells. This exacerbates tear film instability and drives the cycle of events that perpetuate the condition. Traditional approaches to counteracting tear hyperosmolarity in DED include use of hypotonic tear substitutes, which have relatively short persistence in the eye. More recent attempts to counteract tear hyperosmolarity in DED have included osmoprotectants, small organic molecules that are used in many cell types throughout the natural world to restore cell volume and stabilize protein function, allowing adaptation to hyperosmolarity. There is now an expanding pool of clinical data on the efficacy of DED therapies that include osmoprotectants such as erythritol, taurine, trehalose and L-carnitine. Osmoprotectants in DED may directly protect cells against hyperosmolarity and thereby promote exit from the vicious circle of DED physiopathology.
authors.affiliation: Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts and Vision Institute, Paris, France. Electronic address: baudouin@quinze-vingts.fr.
authors.forename: Christophe
authors.initials: C
authors.lastname: Baudouin
authors.forename: Pasquale
authors.initials: P
authors.lastname: Aragona
authors.forename: Elisabeth M
authors.initials: EM
authors.lastname: Messmer
authors.forename: Alan
authors.initials: A
authors.lastname: Tomlinson
authors.forename: Margarita
authors.initials: M
authors.lastname: Calonge
authors.forename: Kostas G
authors.initials: KG
authors.lastname: Boboridis
authors.forename: Yonca A
authors.initials: YA
authors.lastname: Akova
authors.forename: Gerd
authors.initials: G
authors.lastname: Geerling
authors.forename: Marc
authors.initials: M
authors.lastname: Labetoulle
authors.forename: Maurizio
authors.initials: M
authors.lastname: Rolando
mesh_terms: D015352:Dry Eye Syndromes / Q000209:etiology / Q000503:physiopathology / Q000628:therapy; D020397:Goblet Cells / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D009994:Osmolar Concentration; D064587:Osmoregulation / Q000502:physiology*; D013666:Tears / Q000502:physiology*
keywords: L-carnitine; compatible solutes; dry eye disease; erythritol; osmoprotection; osmoregulation; tear film instability; tear hyperosmolarity